Process for directly producing ammonia



Dec. 25, 1928.

C OTTO PROCESS FOR DIRECTLY PRODUCING AMMONIA ATTORNEY Patented Dec. 25, 1928.

UNITED STATES PATENT OFFICE.

CARL korrro, or ESSEN-EUHR, aannemer.`

PROCESS FOR DIRECTLY IRODUCING AMMONIA.

v Application led August 15, 1927, SeriaTNo. 212,954, and in Germany August 9, 1926.

tion of thedesired mobile high-grade tar in the hydraulic main is obtained by intensely irrigating the main by water or tar. Wit-lr the .so-called indirect or half-direct ammonia producing processes, in which the production of the ammonia takes place by cooling and washing the distillation gases bygas water, the treatment of the gases in the `hy l5 draulicmain is not ditiicult because sufficient quantities of cooled gas water areat disposal for the irrigation of the hydraulic main. More unfavorable conditions, however, prevail with the so-called direct processes, f as in these latter the formation of gas water is avoided as much as possible and the ammonia is obtained almost exclusively by directly washing the distillation gases by sulphuric acid. In the latter processes, there is but little hydraulic main because this `water must be used in circulation, and consequently 'is enriched during the circulation more and more with salts (ammonium chloride). The tar is thus considerably thickened and its` treatment in the tar distillation is rendered very difticult.v Now the invention has for its object to eliminate this drawback. To'this end, the invention substantially consists in a comthe hydraulic main with a special cooling installation for the gas and the condensate.y

In order to allow of the invention to be more easily understood, a preferred embodiment of an installation adapted to carry out the present method, is diagrammatically illustrated by way of example in the drawing which accompanies and forms part of this specification.

Referring now to this drawing, a denotes the hydraulic main to which the distillation gases are supplied. These gases are led to cooler d through a pipe b, having a branch pipe c. From cooler (l the gases pass through pipe e to a tar extractor f and further through pipe g into a saturator h. Through a pipe connected to an outlet socket z', the gas is led away from the saturator h, to other apparatus (not shown) for further recovery of byproducts, such as benzols.

The cooling liquid required for cooling the gas water at disposal for the irrigation of the bination of the known irrigating device for gases in the hydraulic main a and in the vertical section of pipe b is taken from a tank la, into which the branch pipe c opens. The liquid flows through a pipe m to a pump n and is forced by the latter through a pipe o and supplied through branch pipe p and nozzle g into the hydraulic main a spraying it into the main, thus4 replacing the portion of the liquid evaporated therein and, on the other hand through pi e o1 and nozzle r into the vertical sect-ion o pipe b, so as to irrigate the gases-before reaching the cooler. `The tarry condensate depositing in thehydraulic main a Hows through pipes b and c intothe tar receptacle c. The gas liowing through pipe b comes into contact with lthe irrigating liquid supplied by nozzle r to the vertical section of pipe before entering thecooler d. Freshcondensate is thereby produced in the `75 cooler d which is collected in the lower pory tion of cooler d, is there cooled separately and supplied again to receptacle through a pipe 8, s Owing to the different specific gravities v'of the constituents of the condensate, a first separation of the latter into tar and ammonia waterv takes place in the receptacle la. The ammonia water is led olf through the abovementioned pipe m, whilst the deposited tar is taken away through a pipe t into a second separating. vessel u. As the liquids come com pletelyto rest in vessel u owing to the latter eing of suiciently large dimensions, a complete'separation of tar and ammonia water takes place therein.- The heavy tar, depositing on the bottom, is withdrawn through a pipe u. The ammonia water, collects above the tar, and is taken ott' through a pipe l. The steps in the described process for treating the distillation gases of coal gas producing furnaces for directly producing ammonia, which consist in feeding the distillation gases to a gas cooler, cooling them in the gas cooler so as to obtain a quantity of fresh condensate, feeding one part of the corr densate to the hydraulic main, thus replao ing the portion of the liquid evaporated therein, feeding another partof the condensate to the pipe leading to the cooler, so as to irrigate the gases, and returning the condensate to the cooler with a. fresh supply of gas.l

to the hydraulic main, thus replacing the por- 10 tion of the liquid evaporated therein, feeding another part of the condensate to the pipe leading to the cooler, and returning the condensate to the cooler with a fresh supply of In testimony whereof, I have signed my name to this specification.

CARL OTTO. 

